GPIO interrupt loss

RE: GPIO interrupt loss

Susheel Nuguru — Mon, 31 Aug 2015 10:00:07 GMT

The possible reasons are

the gpio is not configured correctly to trigger an interrupt. But this reason will become invalid if you have seen interrupts sometimes.
you code has a state machine in your code that is disabling the interrupt.

3)ARM cortex will latch the interrupt, but if the interrupt happens two times before its ISR starts then the latter interrupt will be lost as it will be set to pending bit in NVIC only once. Yes in this case we can look at it as a loss of interrupt as the interrupt was fired too frequently and did not consider that the softdevice could delay interrupts.

RE: GPIO interrupt loss

jimlin — Mon, 31 Aug 2015 09:47:27 GMT

Thanks for reply. But, it seems lost in fact, for the GPIO has been set from low to high, but no interrupt triggle, for I added another GPIO toggle in the interrupt service while nothing happened. Any other possible?

RE: GPIO interrupt loss

Susheel Nuguru — Fri, 28 Aug 2015 08:49:11 GMT

SD can delay app interrupt because SD interrupts have higher priority than app interrupts. i do not think that any interrupts are lost.